Medical fluid flow systems often employ fluid flow connectors, such as Luer connectors, to readily connect components in a liquid leak-proof manner. Compatible connectors typically include a male connector and a female connector. The male connector features a conical male member having a Luer taper that corresponds to the Luer taper of the socket of the female connector. Fluid flow passages within the connectors communicate with openings in the tip of the tapered male member and the inner end wall of the socket of the female connector.
The male and female Luer connectors are joined by inserting the male conical member into the female socket and pushing the two connectors together. The two connectors are secured together by the friction of their mating tapered surfaces. Although such a connection may be suitable for many medical purposes, it is common to employ additional retaining or locking features to hold the male and female Luer connectors together and reduce the risk of accidental disconnection. For example, an internally threaded collar may be provided on one of the connectors and mating threads on the exterior surface of the other connector. Such connectors are commonly referred to as Luer lock connectors.
Industry standards have been established for standardizing the dimensions of Luer connectors and Luer lock connectors for use in medical equipment. An example of such a standard is the International Organization for Standardization International Standard ISO 594.
An example of an ISO 594 male connector is indicated in general at 30 in FIGS. 1 and 2, and includes a conical member 32 with a Luer taper. An annular collar 34 is provided with threads 36 on the inward facing surface. A shaft portion 38 includes a fluid flow passage 42 that is in fluid communication with a flow passage 44 formed in conical member 32. The shaft portion 38 is adapted to be connected to tubing or other medical fluid flow components.
An example of an ISO 594 female connector is indicated in general at 50 in FIGS. 3 and 4, and includes a cylindrical portion 52 having a socket 54 that features a Luer taper and receives the conical member 32 of FIGS. 1 and 2. The exterior surface of the cylindrical portion is provided with threads 56 that are compatible with the threads 36 of FIGS. 1 and 2. A body portion 58 includes a fluid flow passage 62 that is in fluid communication with socket 54 through the inner end thereof. The body portion 58 is adapted to be connected to tubing or other medical fluid flow components. Also either the male or female connector may be actually integral with a medical flow component. For example, a syringe may have a one-piece molded plastic barrel that terminates with a male Luer lock connector.
FIG. 5 illustrates the ISO 594 male Luer connector 30 of FIGS. 1 and 2 joined to the ISO 594 female Luer connector 50 of FIGS. 3 and 4. The tapered conical member 32 of the male connector is received within, and engages the inner surface of, the tapered socket 54 of the female connector, while the threads 56 of the female connector engage the threads 36 of the collar 34 of the male connector.
A new international standard for Luer connectors has recently been introduced or proposed, and is particularly directed to connectors used in apheresis procedures, where blood is withdrawn from a donor, a portion (such as plasma, leukocytes, or platelets) is separated and retained, and the remainder is re-transfused into the donor. The new standard, International Standard ISO 18250, relates to a male apheresis Luer connector and a female apheresis Luer connector for use in apheresis disposable sets and other apheresis components.
An example of an ISO 18250 male Luer connector is indicated in general at 70 in FIGS. 6 and 7, and includes a conical member 72 with a tapered portion and a larger diameter annular offset or shoulder portion 73. An annular collar 74 is provided with threads 76 on the exterior surface. A shaft portion 78 includes a fluid flow passage 82 that is in fluid communication with a flow passage 84 formed in conical member 72. The shaft portion 78 is adapted to be connected to tubing or other medical fluid flow components.
An example of an ISO 18250 female Luer connector is indicated in general at 90 in FIGS. 8 and 9, and includes a cylindrical portion 92 having a socket that features a tapered portion 93 and a taper offset entry portion 95 having an enlarged diameter than tapered portion 93. Socket tapered portion 93 receives the conical member 72 of FIGS. 6 and 7 while the socket offset portion 95 receives the annular shoulder portion 73 of FIG. 7. An annular collar 94 is provided with threads 96 on the inward facing surface that are compatible with the threads 76 of FIGS. 6 and 7. A shaft portion 98 is adapted to be connected to tubing or other medical fluid flow components.
FIG. 10 illustrates the ISO 18250 male Luer connector 70 of FIGS. 6 and 7 joined to the ISO 18250 female Luer connector 90 of FIGS. 8 and 9. The tapered conical member 72 of the male connector is received within, and engages the inner surface of, the socket tapered portion 93 of the female connector, while the threads 96 of the collar 94 of the female connector engage the threads 76 of the collar 74 of the male connector. In addition, the socket offset portion 95 of the female connector receives and engages the annular shoulder portion 73 of the male connector.
The intent of ISO 18250 is that all apheresis disposable sets will eventually use ISO 18250 male and female Luer connectors. Most apheresis disposable sets, however, currently use ISO 594 Luer connectors, which are incompatible with the ISO 18250 connectors. For example, as may be seen by a comparison of FIGS. 1 and 2 with FIGS. 6 and 7, the collar of the ISO 594 male Luer connector has threads on the inner surface, while the collar of the ISO 18250 male apheresis Luer connector has threads on the exterior surface. Likewise, a comparison of FIGS. 3 and 4 with FIGS. 8 and 9 reveals that the ISO 594 female Luer connector has threads on the exterior surface while the ISO 18250 female apheresis Luer connector has threads on the inner surface of a collar. Furthermore, the annular shoulder portions 73 (FIG. 7) of the ISO 18250 male Luer connector and the corresponding socket offset portion 95 (FIG. 9) of the ISO 18250 female Luer connector are missing from the male and female ISO 594 Luer connectors. In addition, dimensional differences exist between the ISO 594 and the ISO 18250 Luer connectors.
A further issue exists in that most disposable apheresis sets are used in conjunction with separate solution bags. A proper connection between the two requires compatible connectors (i.e. a female connector and male connector of the same type or configuration). For example, if a solution bag has an ISO 594 female Luer connector, then the part of the disposable set that feeds into the connection must have an ISO 594 male Luer connector. Most solution bags used with apheresis disposable sets currently use either an ISO 594 male Luer connector or an ISO 594 female Luer connector, so a compatibility issue exists with respect to disposable apheresis sets that feature ISO 18250 Luer connectors.
The above problems are magnified in that a long time period will likely be required for manufacturers of medical components to changeover to the ISO 18250 standard. In addition, some companies may choose not to follow the new ISO 18250 standard at all. This may result in a supply chain problem or disruption. As an example, a medical center may order solution bags from a first company that has changed over to the ISO 18250 standard. The medical center may also order apheresis disposable sets from a second company that still uses ISO 594 Luer connectors. In such a situation, the disposable set will not be able to connect to the solution bag during an apheresis procedure. This may require the medical center to stock duplicative items having different connector configurations, increasing cost, wastage and the risk of faulty connections of incompatible connectors.